Abstract: Welded joints of titanium alloy are used in ships which have requirements on good resistance to impact and fatigue,yet some structural parts have large thickness,and the traditional welding technical efficiency is low and difficult to guarantee the quality of welding. Vacuum electron beam welding technology has advantages in these respects. This article describes the characteristics of the electron beam welding of titanium alloy and its advantages in marine applications,especially in a large heavy plate welding with outstanding resistance to impact and fatigue. Long service life and reliability are aimed when electron beam welding is employed for thick plate welded structure of titanium alloy.